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A First-in-Class Approach to FcRn
Efgartigimod is designed as a first-in-class antibody fragment to target the neonatal Fc receptor (FcRn). Efgartigimod is being evaluated for the treatment of people living with underserved diseases with confirmed presence of pathogenic immunoglobulin G, IgG autoantibodies, where a severe unmet medical need exists.
Current argenx Pipeline Progress
No results
Mechanism of Action
Efgartigimod is a human IgG1 antibody Fc fragment that has been engineered for increased affinity to FcRn, compared to endogenous IgG, and is uniquely composed of the only part of the IgG antibody that normally binds FcRn. Efgartigimod selectively reduces IgG by blocking FcRn-mediated IgG recycling.
- Efgartigimod and IgG are internalized into the cell
- Efgartigimod outcompetes endogenous IgG antibodies and pathogenic IgG autoantibodies for binding to FcRn, due to increased affinity to FcRn
- When bound to FcRn, efgartigimod and IgG escape lysosomal degradation
- Remaining unbound IgG and efgartigimod are degraded in the lysosome
- Efgartigimod and fewer IgGs are recycled back into circulation
Clinical Trials
argenx is running clinical trials of efgartigimod in development for a range of long-overlooked diseases. For more info on clinical trials with efgartigimod, please click the link below.
Publications
Explore the peer-reviewed publications behind the clinical development and outcomes of efgartigimod and more in long-overlooked diseases.
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